share resources across routes safely (async + cleanup)

How to

• Create app-wide singletons in lifespan (e.g., database engine, Kafka producer) and clean them up on shutdown.
• Provide per-request resources via async-generator dependencies that open/yield/close per call.

Example

from sqlalchemy.ext.asyncio import create_async_engine, AsyncEngine, AsyncConnection
from lihil import Lihil, Route

async def lifespan(app: Lihil):
    app.engine = create_async_engine("sqlite+aiosqlite:///test.db")
    yield
    await app.engine.dispose()

async def get_conn(engine: AsyncEngine) -> AsyncConnection:
    async with engine.begin() as conn:
        yield conn

r = Route("/users", deps=[get_conn])

References

• http/lifespan.md:1
• http/endpoint.md:1